Prediagnosis prostate specific antigen velocity is associated with risk of prostate cancer progression following brachytherapy and external beam radiation therapy.

PURPOSE

Prostate specific antigen velocity 2.0 ng/ml per year or greater in the year before prostate cancer diagnosis is associated with cancer specific survival following radical prostatectomy and radiation therapy. We evaluated the relationship between prediagnosis prostate specific antigen velocity and cancer progression following primary radiation therapy.

MATERIALS AND METHODS

We analyzed the records of 24,893 men from a community based prostate cancer screening study and identified 237 with clinically localized prostate cancer who elected primary radiation therapy. Our final cohort consisted of 130 men, including 83 treated with external beam radiation and 47 treated with brachytherapy. Patient specific variables at diagnosis were analyzed for their value in predicting biochemical progression using American Society for Therapeutic and Radiation Oncology criteria.

RESULTS

Mean followup +/- SD was 64 +/- 35 months. Prostate specific antigen at diagnosis, family history of prostate cancer and prediagnosis prostate specific antigen velocity 2.0 ng/ml per year or greater were associated with cancer progression following brachytherapy or external beam radiation. Of men with prostate specific antigen velocity 2.0 ng/ml per year or greater 38% had cancer progression compared to 12% with prostate specific antigen velocity less than 2.0 ng/ml per year (OR 4.3, p = 0.003). The 6-year progression-free survival estimate was 57% in men with prostate specific antigen velocity 2.0 ng/ml per year or greater and 82% in men with prostate specific antigen velocity less than 2.0 ng/ml per year (p < 0.001). On multivariate analysis absolute prostate specific antigen at diagnosis and prostate specific antigen velocity 2.0 ng/ml per year or greater were independently associated with cancer progression in men treated with external beam radiation therapy or brachytherapy.

CONCLUSIONS

Men with a prediagnosis prostate specific antigen velocity of 2.0 ng/ml per year or greater are at increased risk for cancer progression following brachytherapy or external beam radiation compared to men with a prostate specific antigen velocity of less than 2.0 ng/ml per year.